A notable problem in the human foot is that of Hallux Rigidus. Such a problem presents a jammed great toe joint, with arthritis principally on the metatarsal side. The great toe has limited, painful, dorsal flexion, and a bunion or dorsal boney spur may be present, which can be painful. Generally, the Hallux Abductus angle is elevated, and the os sesamoideum (sesamoid bone) may rotate to an abnormal lateral position. An elevated intermetatarsal angle generally results.
Currently available great toe hemi-implants, which have a concave articulating surface and are available in stainless steel, are implanted into the phalangeal side of the joint. Such hemi-implants require a removal of the base of the proximal phalanx, and can engender multiple, documented problems for this presentation, among which can include that the amputation of the base of the proximal phalanx to place the hemi-implant results in a loss of the insertion of the intrinsic muscles. The outcome is loss of digital stability often resulting in jamming of the implant onto the metatarsal head, with pain and again decreased motion occurring. Also, as useful as they are in addressing other presentations, the great toe hemi-implant cannot address the elevation in intermetatarsal angle.
The well known Valenti procedure may be attempted to resect the bunion or spur so as to stop jamming. Since the metatarsal head is partially resected to a flat surface in that procedure, normal dorsiflexion motion is lost, and pain can, and often does, return.
It is also known that the metatarsal mal position seen with Hallux Rigidus can be corrected with a thru and thru metatarsal osteotomy fixated with cannulated screws, which are placed over a K-wire guide pin for proper orientation. The K-wire is removed after the screw is placed over it.
It would be desirable to ameliorate if not solve the Hallux Rigidus problem at least in a reasonable number of presentations. It would be desirable to provide alternatives to the art.